The present disclosure generally relates to the field of electronics. More particularly, an embodiment of the invention relates to controlling substrate surface properties.
Underfilling in some semiconductor packages may be provided by capillary flow. In order to achieve high throughput time, the underfill may be made such that it has a relatively low viscosity and good wetability to substrate solder resist. Moreover, underfill may be dispensed at elevated temperatures, for example, close to 110 degrees C., to enhance underfill flow. This approach may leave a tongue of underfill at the dispense side. This tongue may increase the footprint of the package which may limit the provision of ultra small form factor (USFF) semiconductor packages. Additionally, in stacked die packages, the die-attach bleed-out onto wire bond pads may be a critical issue that may impact the ability to develop small form factor stacked die packages.